The present invention relates generally to sprinklers and more particularly to an impact sprinkler having several improved features.
Impact sprinklers are well known in the art. A typical impact sprinkler includes a main body, usually mounted for rotation, having a nozzle and a journal pin about which a water deflector is pivotally mounted. The water deflector is generally made up of three segments, i.e., opposite end segments, one of which is commonly referred to as a water deflecting segment or deflector spoon and the other of which is commonly referred to as a counterbalance arm, and a central segment which is disposed around the journal pin. This central segment, referred to as a bearing segment, supports the end segments for pivotal movement such that the deflector spoon moves into and out of a jet of water issuing from the sprinkler nozzle.
Heretofore, most water deflectors were constructed of brass. A typical brass deflector having a conventionally designed water deflector spoon provides a specific and satisfactory water distribution pattern around the sprinkler, in the outlying areas of the pattern as well as close in. More recently, because of cost and availability, many sprinkler manufacturers have been replacing their brass deflectors with more economical plastic deflectors, maintaining substantially the same design, especially with respect to the deflector spoon.
Applicant has discovered that, as a result of this change in material from brass to plastic, the water distribution pattern of the sprinkler changed significantly, even though the deflector design remained substantially the same. More specifically, applicant discovered that the substantial reduction in weight in converting over from a brass deflector to a plastic deflector produced a significant increase in what is commonly referred to as deflector rate of impact, i.e., the number of times the deflector spoon moves into and out of the water jet per given unit of time. This means that more water is being deflected by plastic deflectors than brass deflectors causing a significant reduction in the amount of water reaching the outlying areas of the water distribution pattern, or stated conversely, a significant increase of water is directed to areas close to the sprinkler. In this regard, as a general rule, water which reaches the outlying area of the pattern is the water which is undeflected or which is only slightly deflected. As will be seen hereafter, one feature of the present invention resides in an uncomplicated and economical change in the design of the plastic deflector spoon so as to significantly improve the water distribution pattern, specifically at the outlying areas of the pattern.
Another feature of the present invention resides in the bearing segment of the water deflector. More specifically, one drawback in heretofore provided deflectors pivotally mounted around a journal pin is that if abrasive material lodges between the journal pin and the deflector, specifically the bearing surface of the deflector surrounding the pin, thus foreign material can possibly cause increased wear of the components and/or possibly prevent the deflector from pivoting. While this drawback is not limited to plastic deflectors, the conversion to plastic deflectors certainly magnifies the drawback, especially from the standpoint of wear. As will be seen hereinafter, a second feature of the invention resides in an uncomplicated and economical modification of the deflector to minimize the possibility of abrasive materials or other debris permanently lodging between the journal pin and bearing surface of the deflector, possibly resulting in undue wear and/or damage generally.